(a) Field of the Invention
The present invention innovatively discloses that the first asynchronous AC induction electrical machine is installed with main winding and control winding on its magnetic field, wherein main winding is the main driving winding on the rotor of the asynchronous AC induction electrical machine, while its control winding is series connected with the main winding of the neighboring second asynchronous AC induction electrical machine, the control winding and the electrical machine's own main winding are installed at the same polar axis, or on the axis with electrical angle difference, wherein the two can be selected according to operating performance requirements as 1) combination for assisting excitation at same polarities, or 2) combination at opposite polarities for differential excitation, while the control winding being relatively installed on the second asynchronous winding induction electrical machine and the main winding of the first electrical machine winding appear to be wound on the same polar axis or on the axis with electrical angle difference, wherein the two can be selected according to operating performance requirements as 1) combination for assisting excitation at same polarities, or 2) combination at opposite polarities for differential excitation.
(b) Description of the Prior Art
When the conventional multiple asynchronous AC induction electrical machines being operated for motor or generator functions in parallel connection, each electrical machine is operated independently without mutual affections or interactions for particular performance.